Libre office Writer is clearing my custom properties

I use LibreOffice within the process of our document management system.
At a certain moment we update the document with python docx and set some custom properties.

Later on, if I open the document, update and save it with LibreOffice, the custom properties are cleared, while this does not happen if I use Microsoft word.

I have noticed this question which is exactly the same case, but which was closed long ago: Custom Properties Cleared when Saving

I have also gone through the bug page pointed at, there, and tried the old version of LibreOffice mentionned as the one providing good results (version, to not avail.

Please can anybody help ?


And regards


Note : Used version of LibreOffice is 6.4.6

Which properties are being overwritten?
Could you provide example files. One with properties and one without?

Thanks for interest

I am using a little python script with Python-docx to set and read my property

Line to set the property : document.core_properties.identifier = inputvalue
Line to get the property : return document.core_properties.identifier

I will attach two examples of files with and without the identifier property. For the second file, the code to get the property yields nothing. And this happen after the file has been open and saved with LibreOffice.

I played around a bit with the custom document properties and created a docx document (in LO) with some custom properties (key:value pairs) and safed that docx as an odt file and even resafed it as an docx again. The Properties on saving as an odt and docx could still be accessed and seemed to stay intact. Now i am curious how your document compare.


Always use the native, international Standard (ISO) ODF file formats when you use the LibreOffice.

I would like to
But I am not the only decision-maker
And It will take incredibly more time to make all my users understand it, rather than fixing the thing at my level. I have started the education process, since I am engaged to Free Softwares. But, it will take time